In a message dated 11/9/2004 9:38:00 AM US Mountain Standard Time,
k9ay@k9ay.com writes:
While common-mode feedline pickup is a known culprit for this type of noise,
I'll put better odds on direct radiation. The quick test is whether the
noise changes as the pattern is switched. If it does, start fixing the
offending equipment; if the noise stays about the same, work on the feedline
issues, too. It's also possible that the noise is not radiated from a
single point -- switching power supplies with common-mode problems can use
your entire home's AC wiring as an antenna.
In my own installation, the loops are within 30 feet of the house and 40-50
feet from the nearest power pole, so I hear some noise. The noise drops
considerably when the loops are directed away from its source, so I know
it's radiated, not conducted.
73, Gary
K9AY
Tnx for the response, Gary. By the way, I couldnt be happier with the loops.
They sure work "as advertised". Only this noise issue to deal with and I have
been using a workaround for that, my old laptop which is as quiet as a
churchmouse. ;-) I do want to get the noise issue settled though so I can use
the
newer, more powerful computer.
The Loops are about 100 ft from the house and the noise stays abt the same
when I switch loop directions. So, looks like I have two fixes to work on. All
underground electrical service in this area with the closest pole being at
least 1/4 mile away.
Oh, comment on this if you could. The placement of the loops, because of a
pool and other things in the backyard, had to be over where two of my 160m
Inverted L radials (on the gnd, not buried) travel. Could this be another
problem?
I only have 16 radials on the L right now. Coupling problem? The horizontal
portion of the L is, about, 60' from the closest loop.
Tnx for your response!
73, Bob K8IA
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